Deepest Anchoring

Submarine tom,

What kind of current are typical, 5-6 knots??? You have any other ideas?

 

Well, anchoring in five knots is problematic and potentially very dangerous. I believe that there are downriggers that will follow a bottom contour. Try drifting over this camara down but have a break-away in case it hangs. It will stun you how hard it is to get something down in even 2 knots anchored.

 

My original language is French, i may have missed the sense of the question, or maybe as your post let it suggest i am the forum idiot ?

My answer refers to a dynamic anchoring solution opposing two forces, a propulsion to a drogue, using an auto pilot+GPS
In case of the jordan you could regulate traction to any kind of current
The drogue opposed to motor will slow et regulate the motion lowering wind effect, and will reduce the movement to one axis instead of 2
Ideally you need an operator to control trust applied

In fact i would imagine that anchoring the rov and the boat will be two different task.
Dynamic for the boat
Static (rope and a weight) for rov

By the way, in french a drogue is called "floating/buoyant anchor"

http://www.jordanseriesdrogue.com/


Aaaaaaarrrrrrhhhh !!!
Yours Sincerly !
François

 

Currents

mydauphin,

I have no idea what currents are like in your area.

Look on a nautical chart or get some local information from locals.

If they are low and the wind is calm, you could try a drift dive providing

your surface currents match your currents at depth.

Our currents here on the southern west coast of Canada can get up to 20

knots in places but typically are not more than 5-6 on ebb tides.

Do some research. Good luck, don't loose that ROV!

Tom

 

????

mydauphin,

I just re-read the second question in your post.

Yes, I have lots of ideas.

Could you be more spacific?

Tom

 

What a nonsense!

The jordan drogue is a good stabilizer in heavy weather, but what shall be the function if you like to stay over a fixed position (anchor)? The drogue works under speed (or against a current) only, otherwise its a wet towel in the drink. And if there is a current, the stuff will counteract the anchoring efforts, it will move the boat. And what means "motoring slowly" ? "active stability" ? Active stabilisation is a very different issue.

Regards
Richard

 

mai the 8 - 1945

The armistice was signed.
Did you miss this information ?

 

that was pretty funny K

but Apex has a point a sea anchor ( drogue ) does no good in a current if your after remaining on station

if anything its going to force you to drag

not a good situation

so points for Apex on technical merit although you get an A for a good sense of humor K and being a good sport

 

Touche'

 

Controlling current is easier than wind because it is more constant
For wind ?
Hope there is current too !
For current
Drogue will also allow you to move on engine as low as 0.1, 0.5 or 1 Knt.
Weight at the end of the drogue line is supported by a buoy as speed is not enough

I think it is not such a wrong way to search if you do not have a computerised HÜBNER-BRAUN

Cheers !

 

You may repeat that as often you want, it still is NONSENSE! As Apex mentioned above.
And do not ask me for the 8th of May, a good joke cannot conceal your ignorance.
Hägar

 

mydauphin,

Go get a copy of the SupSalv Navy Salvage Manual Vol 4, though 400' TWD is not really all that deep. To put a ROV on the bottom in what I pursume is the costal shelf will require a 4 point moor and a calculation of trail distance. At that depth, for most small ROV's, the umbilical drag will far excede the thrust capability (and most likely your boats hull drag, especially if you are on the east coast for Florida where the Gulf Stream could be 2 knts in water that shallow, otherwise currents rarely excede 1.5 knots except in channels, and most likely under a knot on the shelf.). For a 50hp ROV and an OSV with dynamic stationkeeping this is not much of a challange, for a 0.25hp "flying eye" over the side of a Bayliner, this could be a signifcant challange.

 

ok may be a dumb question
but why the umbilical
cant modulated sonar signals do the job just fine

 

We're not there for a reasonable amount of money yet, Boston (that I know).
The manual ("...currents rarely excede[sic]1.5 knots except in channels...", "...four point moor...")...has zero application here - sorry.
Just wondering...could there be ONE thread on this site where people with legitimate possibilities for solutions prevail over people just Googling **** to feign an impressive bank of knowledge?

 

If it was easy Mark, everyone would have done it by now. It is difficult and that is why the US Navy has an Advanced Undersea Systems Program Office, PMS 394, just to handle these types of things. FWIW, it is my policy to "teach a man to fish" rather than just hand him a squid, because bandwidth is too small to pass a squid anyway and wouldn't feed him much, bits being so tiny. Only a fool doesn't learn from and build on the work done before.

As for the spelling..shrug..it is not what I'm paid for, especially when charitably giving advice to someone who asked. You should see my drafts when I can't type fast enough to keep up with my thoughts. LOL.